<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <h1>999</h1>
    <script>
        //1.获取body
       let bodyEl=  document.body
       //2.获取html
         let htmls=  document.documentElement
           console.log(htmls);
    </script>
</body>
</html>